Apparatus for measuring the human foot



Aug. 14, 1956 M. 1.500s

APPARATUS FOR MEASURING THE HUMAN FOOT Filed June 29, 1955 4Sheets-Sheet 1 Aug. 14, 1956 M. LEDOS APPARATUS FOR MEASURING THE HUMANFOOT Filed June 29, 1955 4 Shets-Sheet 2 mo J m\v r9 Aug. 14, 1956 M.LEDOS APPARATUS FOR MEASURING THE HUMAN FOOT Filed June 29, 1955 4Sheets-Sheet 3 ONRQQQNX, o

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Aug. 14-, 1956 M. LEDOS APPARATUS FOR MEASURING THE HUMAN FOOT 4Sheets-Sheet 4 Filed June 29, 1955 F IG.6

United States Patent APPARATUS FOR NIEASURING THE HUMAN FOOT MauriceLedos, Paris, France Application June 29, 1955, Serial No. 518,903

12 Claims. (Cl. 33-3) The invention relates to an improved apparatus forthe measurement of human feet.

Up to the present time, for measuring feet, only very elementary kindsof apparatus were available such as apparatus of the kind known ascaliper slide-gauges or apparatus derived from such instruments andcomprising a plate provided with two cursors arranged flat on the platein two perpendicular directions. With apparatus of this kind, only thetotal length of the foot and its maximum width (coarsely at the level ofthe metatarsal heads) were measured.

Such apparatus is quite primitive and inadequate since it gives bydirect reading only one measurement or at the most two measurements,namely the length of the foot and the maximum width of the foot(coarsely at the level of the metatarsal heads); in addition, this lastmeasurement is frequently rendered inaccurate by the presence of thehallux valgus which considerably increases the width of the foot at thispoint, and does not give any indication of the differential proportionsof the width, so that, if account is taken only of the length of thefoot and its maximum width at this point, in the manufacture or thechoice of a shoe intended to fit a given foot, it will well beunderstood that in practice the shoe cannot be suitably adapted to thefoot for which it is intended.

The invention has for its purpose to satisfy this need by means of animproved apparatus which enables simultaneous measurement to be made,not only of the width of the foot at a number of important points of itsanatomy, but also the height of important points on its upper face andon the arch of the foot.

These points on the anatomy of the foot which have been referred to asimportant have already been determined with the greatest care by thepresent applicant during the course of previous and very extensiveresearches. It was found during these researches that, in plan, the footis always contained in a rectangular trapezium, of which the angle 0: ofthe two non-parallel sides is, except in really exceptional cases,included between 11 grades and 15 grades for adults (see Figure 1). Thisangle may attain 17 grades in the case of small children. In addition,the height of this trapezium is equal to half the corresponding heightof the triangle in which the trapezium is formed. Further, the upperface of the foot forms, with the lower face, an angle 20: which is twicethe angle previously referred to.

Starting from the rear face of the heel, it is found that the point ofsupport of the heel on the ground is located in the axis of the foot atthe rear fifth on the length L of the foot, that is to say at the pointof support of the base of the calcaneum; that the highest point of thearch of the foot is located at a distance from said heel rear faceapproximately equal to one-third of the length L; that the highest pointof the upper surface of the foot (the first 2 ,758,376 Patented Aug. 14,1956 cuneiform bone, a particularly sensitive point) is located at adistance approximately equal to half the length L; that the internallateral protuberance of the hallux valgus is located at a distancecomprised approximately between two-thirds and three-quarters of thelength L. This point corresponds furthermore to the metatarso-phalangealjoint of the big toe, the joints of all the metatarsals beingfurthermore arranged in an arc of a circle and the metatarsalphalangealjoint of the fifth toe being located at a distance from the rear face ofthe heel, which is approximately equal to three-fifths of the length Lof the foot.

In addition, if the plan view of the foot is considered, it is foundthat the vertical plane passing through the bisector of the angle 0!.contains the point M which is the most important point of the arch ofthe foot (the key of the arch). A further important point of the arch ofthe foot is also the point shown at N, which is located in the verticalplane passing through the axis of the big toe, that is to say the planewhich makes an angle with the plane of the internal face of the footwhich approximately equal to one-sixth of the angle a.

It is also an advantage to know the Width of the foot at one-fifth ofits length from the rear face of the heel, since this width correspondsto the widest portion of the heel, and to the axis of bending of thefoot on the leg; the width of the foot at one-third of its length andwhich corresponds to a concave portion of the external face of the foot;and the width of the foot at half and at threefifths of its length.

The invention has for its object an apparatus by means of which thepositions of the points as well as the values of the various mentioneddimensions referred to above may be determined in the form of precisemeasurements.

This apparatus automatically takes account of the fact that the linearand angular proportions referred to above are always respected, apartfrom a few rare exceptions. It comprises a set of pivoted bars, thepivotal point of which may be brought to a distance from the rear faceof the heel equal to the length of the foot and which corresponds to theapex of the angle in which the foot is contained. Each of these barscarries a sliding feeler the position of which is determined by a devicewhich ensures the proportionality of the lengths referred to, the saidsliding feelers being arranged to be applied in contact with.

the corresponding points of the external face of the foot so that theangular position of the said bars gives an indication of the width ofthe foot at the corresponding points, and, in consequence, the relationbetween these widths.

The invention will be better understood with reference to thedescription which follows and by a study of the attached drawings whichshow by way of example, and not in any sense of limitation, one form ofembodiment of the invention. In these drawings:

Figures 1 and 2 show the geometry of the foot as a whole and in itsessential elements.

Figure 3 is a plan View of the apparatus in accordance with theinvention, which enables an instantaneous reading to be obtained of allthe important dimensions of the foot.

Figure 4 is a profile view of the appartus.

Figure 5 is a cross-section taken along the line 55 of Figure 3.

Figure 6 is a cross-section following the line 66 of Figure 3.

Figure 7 shows in perspective the assembly of one of the devices whichenable the height of the arch of the foot to be measured at a number ofpoints.

If reference is now made to Figure 3, the apparatus in accordance withthe invention is shown in plan, this apparatus enabling simultaneousmeasurement to be made of the right foot and the left foot of a personand having for that reason a longitudinal plane of symmetry. At

3 each side of this" lane or s'y'r'nmetry are located two plates"- 1and" 2 ('see Figure 4) which are respectivelyintended to receive therightand the left foot and which are supported by a base memlrie'r 3. l

The niernb'eis which are disposed on one sidh only of' the saiilplatieof sym-ihetty will n w Be desei-ihed indetail it being understoo thatsymmetrically arrange-u members are ptuvid'ed onthe other sideo'f theapparatus.

Iii addition; in the vertical plane of symmetry, there is arranged amainthreaded adjustment rod 4 provided at itstwoext'remi'ti'es with twothreaded portions of which one, thopuhtion s, isthreaded with aleft-hand thread having a pitehand theother, thepo'rtioii 6*,istlir'eaKiled right-hand a thread or tliesu ne pitch p. The threadedtoo 4 is pivotally-riiountedat itstwoeiirernities in the liase 3- andirtiiay he rot'atedli rneuus of a control cranli lltiridle 7 Oil thethreaded portion 5 is engaged the inner threadilig or a cursor 8(seeal-sh' Figures 9 and 6) which is siidalil-y mounted inat dove tailslide 9" fixed to the base of die-apparatus. l

The plate 1 is provided with a raised edge 1 2 against Whichthe personplaces the rear face of his heel; The slider 8"m'ovesto front of agraduated scale 13 so that-by the drank-handle 7", the cursor 3 may bebroughtinto contact with the front extremity of the foot, thereby givihd measurement of the length L-of the foot. Since the two ends of thethreaded rod have th're'ad's of opposite direction and 05 the samepitch, the that face of the heel is always located at an equal distancefrorh the cursor 8 and fro'r'r'i a further cursor 1 4 which is" lIl*Set-6W engage: filenf Witlithe threadedport' 6 6f the 1 d 4 and whichmay also slide longitudinally along the apparatus.-

The plate 1 has a further raised edge 16, parallel to the planeofsyni'metry' of the apparatus and act ng: as a supporting surface forthe internal face of the foot. A small vertical plate 17 located in thesame plane as the raised edge 16 is rigidly fixed to'the cursor 8 andextends" the edge 16 in the front part of'the' apparatus: The raisededge 16 and the small plate 17 are provided-with notches 18 and 19respectively which enable the continuity oi the lateral supporting faceconstituted by them to'b'e' ensured in spite of the mobile nature of thesmall pl'ate i=7. The cursor 14 has two spindles 22 22". The spindle 22'is arranged approximately in the extension of the raised edge 16* andthe spindle 22- is symmetrical with the spindle 2 2 with respect to thecentral plane of theapparatus- 01: the spindle 2-2 are pivotalllyrnounted four superposed bars 23 24, 25 and 26 (see Figures 3", 4 and6*).

In addition, four cross members 27, 28', 29,30 are fixed respectively tofour cursors 32-, 33, 34, 35'. The'curisor 33' is engaged on a threadedpart 36 of the rod 4', the pitch of which is equal to p/2, that is tosay half the pitch of the threaded part on which the end cursor 8'isengaged. Whatever angle the' rod 4 may be turned through, providedthat a selected reference point on th'e 'cursor 3'3 has been initiallylocated at a distance from the rear face of theheel of the foot beingexamined, equal to half the distance L which separates the rear face ofthe cursor 8 from the front face of the raised edge 12, the samerelationship will b'e'preserved.

The three other cursors 32, 34 and 35- are respectively engaged on thethreaded parts 37, 38 and 39 of an auxiliary rod 42 which is pivotallymounted at its extremities on the base of the apparatus, andwhich iscoupled for rotation to the main rod 4 through the medium of two equaltoothed Wheels 43, 44-, one of which is keyed on rod 42 and the other onthe rod- 4. Since this coupling causes the rod 42 to turn in theopposite direction to the sense of rotation of the rod 4, the threads ofthe threaded parts 37 38, 39 of the rod 42 are right h'and threadsWhilst the threads of the parts 5 and 36 of the rod 4 are left-handthreads, in order that all the cursors driven by the said threaded partsmay move in the same direction when the operating handle 7 is actuated.

The pitches of the threaded pai'ts 37, 38' and '39 are 7 i Screw i 5 6Pitch 600 z 600 (The pitch values have been given in hundredths ofmillimetres.)

A swivel 45- slides at the some tithe alon the rod 23 and on the crossmember-i 27'. ltn a similar way, three other swivels 46, 47 and 48 sliderespectively along the bar 24 and the cross; member 23, 0'11 the bar 25and the cross member 29, and finally on the bar 26 and the cross member30.

On the swivels 45, 46, 47, 48 are fixed feelers 51, 52, 53 and 54 whichare doubly curved (see Figure 6) so as to avoid the edge of the plate 1and thus come into contact with the external face of the foot to bemeasured (Fi ure 3 The bar 23 i rigidly fixed to a lever 101 which: iscoupled to a pointer 102 through the intermediary of a connecting rod-103-. Theointer 1G2 ivutzll muuut'ed on a spindle 1 64 mounted on a suport 1'65" rigidly fixed to the cursor 14. A raduated shale 1G6 engravedoil-die su port has enables the deflectionof the pointer 102 to be notedand, in conse uence, the ang lar position of the bar 23 whichcorresponds to the value of the angle a; The three other end bars 24,25, 26 are connected respectively in asimilar manner to three pointers1'07, 108, 169.

It will he noted that, when the craulehandle T is turnetfi the cursor i4is displaced together with other members" and, in consequence, thepivotal axis 22 of all thelongitudinal bars is also dis laced. Durinthe" course of this movement, the bars 2 s, 24, 25- and 26 sliderespectively in the swivels 45, 46, 47 add 48-; in addition, the bar 23'also slides in the swivel 70 which is radially retained by the circularslot 60 forine'd in the plate of the apparatus. The bar 55 slides on theswivel 18 and in; the swivel of the antograph, whilst the bar 8! slideson the swivel 92 and in the swivel 88 of the pan tographz- It has alreadbeen seen with reference to Figure t that? it is also important to knowthe" point M which is the point corresponding to the key of the arch ofthe-foot; This point is located in the vertical plane which bisects theangle or in order to obtain this point, a further bar 55 rsee Figure 3)has been provided, this bar also being pivoted upon the spindle of thecilrsor l i. This bar 55 is constantly retained on the bisectur of theangle rotied by the bar 23 and is parallel to the threaded rod 4- whichpassesthrohgh the axis 2 2, by means of" a antor'aph, one half of whichis formed by a lozenge comosed of four pivoted rods 56, 57, 58 and 5,and the other half of which is constituted, for reasons which will begiven later, by two other unequal lozenges, the first of which is formedby four rods 62, 63, 64 and 65, and the second By four shorter rods 66,6'7, 68 and 69. The common oint" or articulation of the two rods 56 and57 ofthe first half or the photograph is located on a spindle 72 whiohisrigidly fixed to a cursor '70 adapted to slide on the hai 23, and theeoiulnuu point of articulation of the two rods 66 and 69 of the smalllozenge of the second half of the pantograph pivots about a spindle 73-which is rigidly tired to the casing 3 or the apparatus. The rods- 63and 64 or the seeond half ofihe pantograph are respectively fixed to therods 58 and 59' of" the first half of the ph to raph, and are disposedin the eit'tensio'ri or theselatter, Whilst the rods 67 and 68' arerespeetively fixed in a similar way to the rods and 62 and are alsoarran ed as their extensions. The common" mas es point of articulationof the rods 58, 59, 63 and 64 is located on an axis 74 fixed to a cursor75 arranged to slide on the extremity of the bar 55. The three spindles72, 75 and 73 are always in a straight line and the dimensions of thevarious rods of the pantograph are so chosen that the spindle 74 islocated at equal distances from the two spindles 72 and 73. The resultis that the bar 55 is always situated on the bisector of the angle apreviously referred to, whatever may be the angular position of the bar23.

The point M, which has been referred to above with reference to Figure1, is thus located above the bar 55 and it has been seen that it must atthe same time be located at a distance from the rear face of the footequal to one-third of the total length L of the foot. For this reason,there has been provided in the arm 29 rigidly fixed to the cursor 34which corresponds to L/3, a longitudinal slot 76 and, in the bar 55, alongitudinal slot 77 in which is arranged to slide a swivel 78 (see alsoFigure 7). The swivel 78 corresponds to the point of intersection of thebar 55 and the arm 29 and is always situated at the same time on thebisector of the angle on already referred to and at a distance L/3 fromthe heel. The swivel 78 carries a vertical tube 79 (see Figure 7) inwhich slides a rod 81 which is terminated at its upper part by a roundedhead 82 and is constantly pushed upwards by a spring (not shown). Therod 81 passes through a rectangular opening 83 (see Figure 3) formed inthe plate 1 and it is coupled at its lower part to an indicating pointer84 through the medium of a control of any kind, such as for example by acontrol 86 of the Bowden type in the apparatus shown in the drawings.The end of the pointer 84 moves in front of a graduated scale 85situated at a suitable part of the base of the apparatus and indicatesthe height of the head 82 above the plate 1. It will thus be understoodthat, when the foot to be measured is resting on the plate 1, the rod81, which is urged upwards by its spring, is applied against the arch ofthe foot, and that the pointer 84 indicates the height of thecorresponding point of the arch of the foot.

In an exactly similar way, the point N, as defined in Figure 1, isdetermined by means of a bar 87 which corresponds to one-sixth of theangle or, by means of a cursor 88 adapted to slide on this bar and whichis rigidly fixed to the common axis of articulation of the two lozengesof the second half of the pantograph, as described above. To this end,it will sufiice to dimension the members of the pantograph in such amanner that the distance of the cursor 88 from the fixed spindle 73 ishalf the distance of the said cursor from the spindle 74 of the cursor75 which slides on the bar 55.

The variations in angular position of the various bars are sufficientlysmall to assume, for the requirements of ordinary use, that the arcs andthe chords which subtend them are equal in length.

The bar 87 is also provided with a slot 91 in which slides a swivel 92which slides at the same time in the slot 76 of the arm 29 of the cursor34. The swivel 92 thus corresponds to the position of the point N ofFig. l, and it is provided with a spring-loaded rod which also passesthrough the opening 83 and which is constructed in the same way as therod 82 which serves in the determination of the point M. This rod iscoupled by a control 93 to a pointer 94, the point of which moves infront of a graduated scale 95. The height of the point N 8f the arch ofthe foot may thus be read-off on the scale At the beginning of thepresent description, it has also been stated that it would be anadvantage to know the height of the first cuneiform bone which islocated on the upper face of the foot, half-way along its length, andalso the height of the point of the upper face of the foot which issituated at two-thirds of its length starting from the rear face of theheel. A measurement of the height of 6 these two points'is obtained byusing the devices 111 and 112, which are similar to scribing gauges andwhich are respectively carried by the cursor 33 and a further cursor 11,which is in screw engagement with the threaded part 10 of the maincontrol rod 5 which has a pitch of same hand as that of the threadedpart 5 and equal to- /3 of the same (a. g. 400 hundredths of onemillimetre). Graduations 114 and 115 enable the heights of the twopoints in question to be indicated. In addition, the device 112 may beadjusted with respect to the cursor 113 in two directions at rightangles to each other in the horizontal plane, by means of two dove-tailslides such as the slide 116 which is shown on Figure 5. Two graduatedscales 117, 118, enable these two perpendicular displacements to beindicated. The trolley which slides on the slide 116 carries a smallplate 120 perpendicular to the plate 1 and intended to measure thelocation of the hallux valgus.

These scribing gauges may be provided with a feeler which moveslaterally so as to measure the thickness of the foot at a number ofpoints corresponding to the second, third, fourth or fifth metatarsal.

The operation of the apparatus which has been described above is asfollows:

In the first place, it is desirable to state that when the weight of thebody rests on the feet, the arches of the feet undergo a certainflattening action. In accordance with the data which it is desired toobtain, the apparatus is arranged so as to be utilised either flat foruse in the standing position and to take account of the proportions ofthe foot in this positon, or in an inclined position with differentdegrees of inclination (by adjustment of the base) so as to take themeasurements of the foot under a moderate pressure in order to obtain agood fitting of the shoe, for example.

To facilitate the placing of the feet in position on the apparatus, thefeelers 51, 52, 53 and 54 are first opened out and the two cursors 8 and14 are widely separated from each other by means of the crank-handle 7.The feet are then placed in position in such manner that the rear faceof the heel is in contact with the raised edge 12 and the internal faceof the foot is in contact with the raised edge 16 and the small plate17. In the case of the hallux valgus, this may be measured by moving thecursor 120 laterally.

The crank-handle 7 is turned so as to bring the cursor 8 in contact withthe extremities of the big-toes. The total length L of the foot may thenbe read-off directly on the graduated scale 13 associated with the endof the said cursor, and this dimension gives the size. All the othercursors will then be automatically located at the positionscorresponding to the desired fractions of the length L by virtue of themechanical design of the device, as described above. Without any furtheroperation, the height of the two points M and N of the arch of the footmay be read-off directly on the graduated scales 85' and 95.

The two sets of feelers 51, 52, 53 and 5d are then brought into contactwith the external surface of the feet. The width of each of the twofeet, at the different points with which the feelers are in contact, maythen be directly read on the graduated scales in front of which move thepointers 102, 107, 108 and 109. It will be simple to measure, by anysuitable known means, the perimeter of the foot at the desired points byusing these feelers as a guide.

Finally, the two scribing-gauges 111 and 112 are lowered until they comeinto contact with the upper surface of the foot, and the correspondingheights of these two points may then be read directly from the graduatedscales 114 and 115.

In conclusion, it will be seen that, whatever may be the length of thefoot and whatever its shape may be, there is immediately obtained themeasurement of the widths and the heights of the foot at thecharacteristic positions of its anatomy, such as defined above. It isclear that an apparatus of this kind, the use of which is strikinglysimple, enables precise indications to beobtained as to the shape andthe dimensions of the foot, and this in a wholly automatic manner.

To sum up, the apparatus which has been described in the foregoing,enables measurement to be made with a high degree of accuracy asfollows:

(1) The real length of the foot (a) When free from weight,

(b) When supporting weight;

(2) The Width of the foot at a number of important points (3) (withoutany implied limitation) (a) Along its internal edge,

(I) At the level of the metatarso-phalangeal joint of. the big toe,

(II). At the level of half the length of the foot,

(III') At the level of the rear third,

(IV) At the level of the rear fifth.

() Along its external edge,

(I) At the level of the metatarso-phalangeal joint of the fifth toe,

(H) At the level of half the length" of the foot,

(III) At the level of the rear third,

(IV) At the level of the rear fifth.

(c) For-the case of the hallux valg'us (deformation of the big toe) (I)By virtue of the lateral movement of the inside feeler located at thispoint, to deter mine the exact value of the lateral p'rotuber ance ofthe hallux valgus,

(II) By' means of the scribing-gauge located at this same" level, theupward protuberance of the hallux valgus' is measured.

(d) In the case of the quintus varus (deformation of the fifth toe), theprotuberance of the metatarso-phalangeal joint of the fifth toe i'smeasured by means of the outside feeler located at this level;

(-4) The thickness ofthe foot,

(a) At thelevel' of the front two-thirds of the length of the foot,

(1)) At the level ofhalf. the length. These measurements are not to betaken in any limiting sense, but they are sufi'icient to determine bydirect reading'on the scribingvgauges, at the same time as the heightof'the foot; the angle of the upper face of the foot.

(5') The exactvalue of the heights-of the arch ofthe foot by means ofthe lower feelers (of which there may beany desired'number)- Theaboveessential measurements enable a complete study of the foot to bemade by establishing by direct reading; amongst other dimensions; thefollowing! llts length;

2Its widths and their proportions;

3-'l' he angle of the rectangular trapezium inwhich the foot can beincluded;

4The angle of the upper part 05 the foot, either along the path of: thecentralbisector, or at any other point;

5-'l he measurements of the perimeters and, in. consequence, thevolumetric measurements of the foot;

6-The principal features'ofthe foot enabling; the determination, amongstother features;

(11) Whether the foot is normal; (17) If the arch has fallen and in whatproportion with respect to a normal foot, this proportion being.

determined with absolute precision; (c) If the camberv of the footisexcessive and,v with precision; in What proportion with respectto-thenormal foot;

(d) The elongation or the shortening of. the foot as a function of'thefalling of the arch or: theexces sive amount of'camber;

8 (e) The exact proportions between the length and the Width;

(f) The proportions as between the widths themselves; j (g) The more orless pronounced spreading of the front transverse arch of the foot; (h)A comparison of the various angles; (i) The proportions of the lengthsof the foot, the front span of the longitudinal arches (internal andexternal measurement) etc.

The graduations' of the apparatus which are given either in degrees orin grades, either in millimeters or in inches, make it universal. Theapparatus may be designed in alarge number of forms from the most simple(a cal iper slide-gauge with lateral members sliding lengthwise andtransversely)" up to the most complicated form, giving a direct readingwith a simple operation, and may be applied to a study of the human footin all the fields of its application; anatomy, physiology,standardisation of footwear, taking measurements, study of shapes, etc.

It will, of course, be understood that the invention is in no way'limited to the forms of embodiment described and shown; numerousalternative forms wilt be readily apparent to those skilled in the art,depending on the applications considered, and without thereby departingfrom the spirit or the scope of the present invention.

What I claim is:

I'. A- foot measuring apparatus comprising" a foot receiving base, anabutment fixedly carried on said base and extending normally withrespectthereto for engagement by-t-he-re'ar race: of the heel of thethe: tube meetsured, a the slider movable to-ancl-fro relative tosaidbase towards and awayfrom said abutment, operating means operativelyconnected to s'aid' toe slider for moving the" same into engagement withthe tip of the big-toe of the foot to be measured; at least oneauxiliary slider also movable to-and-fro relative t'o'said base towardsand away fromthe plane of said abutment between said plane and theplaneof said toeslider, means operatively connected tosaid operatingmeans for moving said auxiliary slider in such a manner that the ratioof the distances between said abutment on one hand, and said toe sliderand said auxiliary slider respectively, on the other hand, has a"constant-predetermined value regardless of the position 05 sai'cl toesliderwith respect to said abutment, a trans verse slider carried bysaid auxiliary slider and movable transversely of thedir'e'ction-ofmovement of" said auxiliary slider, a laterali foot-engaging feelercarried by said trans? verse slider and adagfate'rl to be brought intoconta'ctwiththelateralzfa'ce of thefootto be nieasured first indicatingmeans" earned by said I base and cooperating" with said toe slider forindicating-'thep'osition of said toe slider on said' base, and secondindicating means cooperating with said transverse slider forindicatingthe position of said lateral feeler with respect -to said base.-

2. An apparatus as defined in" claim 1; furthermore comprising. alongitudinal reference abutment against whichv the inner face: of thefoot to be measured is 1 tobeapplied 3'.v An apparatus as defined inclaim 1, wherein two auxiliary: sliders are'pr'ovided, the variabledistancesb'etween-each" ofi said t-w'o sliders and saidabutment beingrespectively one fifth:and three" fifths of the variable'dis tanoebetween said toe s'liden and 'said abutment; wherebya=- measu'reisobtained of the width ofthe foot to be measured: at two predetermin'edlocations of the length thereof namelyg. one fifth (point where the heelrests on" theground) and three fifths (metatarso-phalangeal articula'-tion) thereon fromi therreanface of the heel.

4-. An: apparatus: as" defined in 'claim r, furthermorecomprishigia-tileastone ancillary slider a'ls'o' movable to andsfrorelative to said base toward and away fro'rnflthe' planes oft saidabutment between said planeand the-plane of said toe: slider, meansoperatively connectedto said ancillary sliderfon movingg the same insuch a manner that the ratio of the distances between said abutment onone hand, and said toe slider and said ancillary slider respectively, onthe other hand, has a constant predetermined value regardless of theposition of said toe slider with respect to said abutment, and meanscarried by said ancillary slider and movable toward and away from saidbase for engagement with the upper face of the foot.

5. An apparatus as defined in claim 4, comprising two ancillary sliderslocated at variable distances from said abutment respectively equal toone-half and twothirds of the variable distance between said abutmentand toe slider.

6. An apparatus as defined in claim 1, wherein at least one of saidauxiliary sliders carries an upwardly movabe feeler adapted to measurethe thickness of the foot.

7. An apparatus as claimed in claim 5, wherein said ancillary sliderspaced from said abutment by a variable distance equal to two-thirds ofthe variable distance between said abutment and toe slider carries anupwardly movable feeler adapted to measure the thickness of the footabove the hallux valgus region.

8. An apparatus as claimed in claim 7, wherein said feeler isfurthermore adjustable in two right-angled directions on said ancillaryslider to permit determining the exact location and volume of an halluxvalgus.

9. An apparatus as defined in claim 1, wherein said auxiliary slider islocated at a variable distance from said abutment equal to one-third ofthe variable distance between said abutment and toe slider and whereinsaid laterally adjustable feeler is connected with two upwardlyadjustable feelers through a linkage adapted to keep said upwardlyadjustable feelers at distances from the internal face of the footrespectively equal to one-sixth and one-half of the width of the foot asmeasured by said laterally adjustable feeler.

10. An apparatus as defined in claim 9, wherein said linkage isconstituted by screws of suitable difierential pitches cooperating withnut members integral with said sliders and rotated at equal speeds fromappropriate control means.

11. A foot measuring apparatus comprising a foot receiving base, alongitudinal abutment on said base in a plane extending normally to saidbase for engagement by the inner face of the foot to be measured, a toeslider movable to-and-fro relative to said base towards and away fromsaid abutment, a transverse abutment on said base in a plane extendingnormally to said base for engagement by the rear face of the foot to bemeasured, operating means operatively connected to said too slider formoving the same into engagement with the tip of the big toe of the footto be measured, a pivot the axis of which extends normally to said base,said pivot being mounted for to-and-fro movement in the plane of saidlongitudinal abutment, on the side of said transverse abutment oppositethe side of said toe slider, means for moving said pivot so designed andarranged that the distance between said pivot and said transverseabutment is permanently equal to the distance between said toe sliderand said transverse abutment, a pivoting bar pivotally mounted on saidpivot, at least one auxiliary slider movable toand-fro relative to saidbase toward and away from the plane of said transverse abutment betweensaid plane and the plane of said toe slider, means operatively connectedto said operating means for moving said auxiliary slider in such amanner that the distances between said transverse abutment on one handand said toe slider and said auxiliary slider respectively, on the otherhand, has a constant predetermined value regardless of the position ofsaid toe slider with respect to said transverse abutment, at least onefeeler located in the transverse plane containing said auxiliary sliderand operatively connected both with said auxiliary slider and saidpivoting bar and adapted to be brought into engagement with the outerface of the foot to be measured, and indicating means operativelyconnected to said pivoting bar for indicating the angle between said barand the plane of said longitudinal abutment.

12. An apparatus according to claim 11, wherein said auxiliary slider islocated at a variable distance from said abutment equal to one-third ofthe variable distance between said abutment, the apparatus furthercomprising at least two other bars pivoted on the same pivot as saidpivoting bar and two upwardly adjustable feelers each slidably mountedboth on one of said other bars and on a transverse member of saidauxiliary slider, said three pivoting bars being interconnected througha linkage adapted to keep the variable angles between said other barsand the longitudinal axis of the apparatus, respectively equal toone-sixth and one-half of the angle between said axis and said pivotingbar.

References Cited in the file of this patent UNITED STATES PATENTS1,792,892 Cobb et a1. Feb. 17, 1931 2,657,463 Spencer Nov. 3, 19532,696,051 Perman et a1. Dec. 7, 1954 2,706,856 Cwiak et a1 Apr. 26, 1955

